🐛 The direction of screw axes should align with their glide

Baharis · Jan 22, 2025 · ea7c587 · ea7c587
1 parent 3d003ab
commit ea7c587
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Showing 2 changed files with 4 additions and 2 deletions.
diff --git a/hikari/symmetry/operations.py b/hikari/symmetry/operations.py
@@ -294,7 +294,9 @@ def orientation(self) -> Union[np.ndarray, None]:
             return None
         if o is None:
             return o
-        o = o if sum(o) > 0 else -o
+        o = o if sum(o) >= 0 else -o
+        if self.typ is self.Type.rotoinversion:  # same direction as glide
+            o = o if np.dot(o, self.glide) > 0 else -o
         return o / np.sqrt(sum(o*o))
 
     @property

diff --git a/tests/test_operations.py b/tests/test_operations.py
@@ -142,7 +142,7 @@ def test_sense(self):
         self.assertEqual(self.sg40_a.sense, '')
         self.assertEqual(self.sg40_21.sense, '')
         self.assertEqual(self.sg40_n.sense, '')
-        self.assertEqual(self.sg147_m3.sense, '+')
+        self.assertEqual(self.sg147_m3.sense, '-')
 
     def test_at(self):
         self.assertEqual(self.sg40_a.at(p111).code, 'x+1/2,-y+2,z')